Ultrasonography as a guide during vascular access procedures and in the diagnosis of complications

ECHOTIP: A structured protocol for ultrasound-based tip navigation and tip location during placement of central venous access devices in adult patients

Central venous access devices are routinely used in clinical practice for administration of fluids and medications, for drawing blood samples and for hemodynamic monitoring. The adoption of ultrasound guided venipuncture has significantly reduced procedure-related complications, as documented by the recommendations of most recent guidelines. Ultrasound has also an important role also in other aspects of central venous catheterization, such as in the pre-procedural evaluation of the venous patrimony and in the detection of early and late non-infective complications. Recently, bedside ultrasound has been regarded as a promising tool also for ensuring an accurate and intraprocedural method of tip navigation and tip location. The aim of this paper is to review all the evidence about the accuracy of ultrasound methods for tip navigation and tip location in adult patients, and to suggest a structured standardized protocol for clinical practice.

Ultrasound-guided, long-axis, in-plane, infraclavicular axillary vein cannulation: A 6-year experience

BACKGROUND

Despite its potential advantages, ultrasound-guided cannulation of the axillary vein in the infraclavicular area is still rarely used as an alternative to other techniques. There are few large series demonstrating the safety and feasibility of this approach.

METHODS

Retrospective analysis of data on patients undergoing ultrasound-guided, long-axis, in-plane infraclavicular axillary vein cannulation for the incidence of complications and the failure rate from two secondary-care hospitals.

RESULTS

The analysis included 710 successful attempts of axillary vein long-axis, in-plane, US-guided cannulation, and 24 (3.3%) failed attempts. We recorded a 96.7% success rate with an overall incidence of complications of 13%, mainly malposition (8.1%). There was one case of pneumothorax (0.14%), five cases of arterial puncture (0.7%), and two cases of brachial plexus injury.

CONCLUSIONS

The US-guided axillary central venous cannulation (CVC) access technique can be undertaken successfully in patients, even in challenging circumstances. Taken together with existing work on the utility and safety of this technique, we suggest that it should be adopted more widely in clinical practice.

Incorporating Evidence-based Ultrasound-guided Vascular Access (USGVA) Standards Into the Nurse Anesthetist Armamentarium: A Quality Improvement Project

PURPOSE

This quality improvement (QI) project developed and implemented a hybrid training program, that included online modules and hands-on training for experienced certified registered nurse anesthetists (CRNAs) to increase confidence, knowledge, and competency with ultrasound-guided vascular access (USGVA).

DESIGN

This QI project used a pre-post design. Seventeen volunteer CRNAs participated in USGVA training and education, and a 90-day follow-up assessment was performed.

METHODS

The Revised Standards for Quality Improvement Reporting Excellence (SQUIRE 2.0) guidelines were used as a framework to assess confidence, knowledge, and hands-on competency of 17 CRNAs who regularly place vascular access devices using USGVA in patients with difficult vascular access at a single facility. These assessments were measured at: (1) baseline, (2) immediately after attending a hybrid training educational program, and (3) 90 days after implementation into clinical practice. Additionally, the number of vascular access attempts required for successful placement of peripheral intravenous (PIV) catheters, arterial catheters, and central venous catheters (CVC) with ultrasound assistance over a 90-day period was reviewed.

FINDINGS

Certified registered nurse anesthetists' median confidence score increased significantly from pre- to post-education (P = .009). The confidence reported from post- to 90 days post-education improved, however it did not reach statistical significance (P = .812). The knowledge scores from pre- to post-education indicated significant improvement (P <. 001), as well as from pre- to 90 days post-education (P = .03). However, knowledge scores from post- to 90 days post-education revealed a statistically significant decline (P = .004). The overall median score for hands-on USGVA competency declined from post- to 90 days post-education (P = .109). The number of successful USGVA placements increased from 50% to 80% within a 90-day period.

CONCLUSIONS

The implementation of a USGVA hybrid training and education program improved overall provider confidence, knowledge, and competency. While confidence remained high in the 90-day follow-up, knowledge retention declined. Despite a decline in knowledge retention over time, results showed a significant improvement when compared to baseline scores. Although a decline in hands-on USGVA competency was seen at 90 days posteducation, it was not statistically significant. The percentage of overall successful USGVA placements in clinical practice increased following implementation.

Comparative Effectiveness, Efficiency, and ED Nurse Preference Between Two Methods of Visualization for Midline Catheter Insertion: A Pilot Study

Introduction

Rapid and reliable peripheral IV access is essential for many patients admitted to the emergency department (ED) to ensure administration of life-saving medications, and successful intravenous cannulation can significantly affect patient care.

Objective

The objective of this study was to assess the impact of a continuous needle tracking system on the accuracy, speed, and quality of ultrasound-guided peripheral venous catheter insertions.

Methods

A convenient sample study based on the study setting using simulated tissue was conducted with 49 US-based ED nurses to compare the insertion of a midline catheter using traditional ultrasound guidance versus an advanced needle-tracking technology along with ultrasound guidance. The purpose of this evaluation was to assess the impact of continuous needle tracking system. Informed consent was obtained from all individual participants involved in this study. All participants were made aware that the results may be published. There was no IRB approval for this study. All sources were properly disclosed within the text.

Results

The addition of the advanced needle-tracking technology significantly reduced total insertion attempts, insertion time, backwall penetrations, and redirects (probes to hit the target vein), while improving image clarity and confidence for participants.

Conclusion

The innovative needle-tracking system evaluated in this pilot study has the potential to improve emergent difficult vascular access. EDs should assess the value of this technology to potentially improve the management of difficult intravenous access patients in their settings.

Post-Acute COVID-19 Syndrome for Anesthesiologists: A Narrative Review and a Pragmatic Approach to Clinical Care

Post-acute coronavirus disease 2019 (COVID-19) syndrome is a novel, poorly understood clinical entity with life-impacting ramifications. Patients with this syndrome, also known as "COVID-19 long-haulers," often present with nonspecific ailments involving more than one body system. The most common complaints include dyspnea, fatigue, brain fog, and chest pain. There currently is no single agreed-upon definition for post-acute COVID-19 syndrome, but most agree that criterion for this syndrome is the persistence of mental and physical health consequences after initial infection. Given the millions of acute infections in the United States over the course of the pandemic, perioperative providers will encounter these patients in clinical practice in growing numbers. Symptoms of the COVID-19 long-haulers should not be minimized, as these patients are at higher risk for postoperative respiratory complications and perioperative mortality for up to seven weeks after initial illness. Instead, a cautious multidisciplinary preoperative evaluation should be performed. Perioperative care should be viewed through the prism of best practices already in use, such as avoidance of benzodiazepines in patients with cognitive impairment and use of lung-protective ventilation. Recommendations especially relevant to the COVID-19 long-haulers include assessment of critical care myopathies and neuropathies to determine suitable neuromuscular blocking agents and reversal, preoperative workup of insidious cardiac or pulmonary pathologies in previously healthy patients, and, thorough medication review, particularly of anticoagulation regimens and chronic steroid use. In this article, the authors define the syndrome, synthesize the available scientific evidence, and make pragmatic suggestions regarding the perioperative clinical care of COVID-19 long-haulers.

Point-of-care ultrasound with handheld devices in hematology: a monocentric single-stage phase II study

Point of care ultrasound (PoCUS) with pocket-size devices is an efficient and safe imaging modality that became a standard of care in various clinical settings. However, its implementation in hematology has never been evaluated so far. We conducted a prospective monocentric study aiming to harvest data on its usage and to assess its diagnostic and interventional performance in improving the accuracy of basic physical examination in hematological patients. After a focused training program, six hematologists were trained and conducted this study. Sixty-two patients were included. Only in 19 cases, further specialized imaging was required, whereas, in 43 patients PoCUS was sufficient to address the clinical inquiries. The use of PoCUS devices was assessed for its performance difficulty and usefulness perception with satisfactory outcomes. This study represents a proof-of-concept application of PoCUS in hematology, suggesting benefits over the physical examination.KEY POINTSPoCUS is particularly attractive in a hematological setting because able to improve the accuracy of physical examination.A hematology-focused training in PoCUS using handheld devices can allow hematologists to perform bed-side diagnostic and interventional US-based exams.

The Focused Assessment with Sonography in Cancer (FASC) Examination

Malignant effusions occur frequently in patients with cancer and are important to diagnose and treat. In this report, we describe a novel point-of-care ultrasound (POCUS) protocol to rapidly identify pleural effusion, pericardial effusion, and ascites: The Focused Assessment with Sonography in Cancer (FASC). This protocol utilizes six standard sonographic positions to identify the presence of fluid in common anatomic spaces. The FASC examination is intended for widespread use by oncologists and other clinicians who treat patients with cancer.

Usefulness of doppler techniques in the diagnosis of peripheral iatrogenic pseudoaneurysms secondary to minimally invasive interventional and surgical procedures: imaging findings and diagnostic performance study

The pseudoaneurysm (PA) is a perfused sac directly connecting with the arterial lumen by an interruption of the vessel wall continuity, more commonly secondary to trauma or iatrogenic causes. Aim of our study was to determine the accuracy and usefulness of Doppler techniques in the diagnosis of peripheral iatrogenic PAs secondary to minimally invasive procedures. From a three year prospective research, 20 Duplex Ultrasound (DUS) studies in as many patients presenting with periarterial pulsating mass clinically suspected for PA secondary to minimally invasive procedures were selected. The PA final diagnosis was confirmed by angiography in 12 patients (60% cases), by computed tomography angiography in 5 patients (25%), by surgery in 2 patients (10%), and by magnetic resonance angiography in 1 patient (5%). The vessels involved by PA formation were: common femoral artery in 8 cases (40%); superficial femoral artery in 4 cases (20%); brachial artery in 3 cases (15%); popliteal artery in 2 cases (10%); superficial temporal artery (STA) in 2 cases (10%); dorsal medial digital artery of the foot in 1 case (5%). Our study confirmed the usefulness of doppler techniques in the diagnosis of peripheral iatrogenic PAs. Specifically, a sensitivity of 90-95%, a specificity of 100% and predictive values of 100% (VPP) and 83-90% (VPN) were reported. The radiologist must always suspect a PA in the differential diagnosis of lesions contiguous to an artery vessel. This is to prevent potential complications such as e.g. massive haemorrhage. In this order, DUS allows a careful selection of patients who require to undergo in-depth imaging methods or surgical therapy, thus contributing to a significant reduction of contrast medium and exposure to ionizing radiation.

Peripheral vascular access for therapeutic plasma exchange: A practical approach to increased utilization and selecting the most appropriate vascular access

BACKGROUND

Therapeutic plasma exchange (TPE) is used in the treatment of many diseases. At present, peripheral vascular access (PVA) is an underutilized method of vascular access in TPE. It should be considered more frequently due its relatively low risk for adverse events, particularly infections.

METHODS

The Advancing Vascular Access in Apheresis Working Group met in December 2017 for an extensive review and discussion of vascular access for TPE and developed a "road map" providing detailed information regarding clinical situations in which PVA-based TPE would and would not be appropriate.

RESULTS

The road map is consistent with current recommendations that PVA should be used in combination with TPE whenever possible. PVA should be considered for patients who do not have existing central lines and who are stable. The patient should have peripheral veins that will allow for adequate treatment and must be able to comply with the process of achieving and maintaining peripheral access. There should be expert clinical assessment of veins, and this evaluation may include ultrasound and/or near infrared evaluation. Conditions that would prompt a switch from PVA to an alternate method of venous access include loss of venous access, patient preference, or development of a requirement for very frequent treatment over a long period of time.

CONCLUSIONS

While PVA is not suitable for all patients requiring TPE, it has significant safety advantages over other approaches and should be employed whenever possible.

Effect of ultrasound-guided central venous catheter insertion on the incidence of catheter-related bloodstream infections and mechanical complications

Background

Central venous catheters (CVCs) are necessary for critically ill patients, including those with hematological malignancies. However, CVC insertion is associated with inevitable risks for various adverse events. Whether ultrasound guidance decreases the risk of catheter-related infection remains unclear.

Methods

We observed 395 consecutive CVC insertions between April 2009 and January 2013 in our hematological oncology unit. Because the routine use of ultrasound guidance upon CVC insertion was adopted based on our hospital guidelines implemented after 2012, the research period was divided into before December 2011 (early term) and after January 2012 (late term).

Results

Underlying diseases included hematological malignancies and immunological disorders. In total, 235 and 160 cases were included in the early- and late term groups, respectively. The median insertion duration was 26 days (range, 2–126 days) and 18 days (range, 2–104 days) in the early- and late term groups, respectively. The internal jugular, subclavian, and femoral veins were the sites of 22.6, 40.2, and 25.7% of the insertions in the early term group and 32.3, 16.9, and 25.4% of the insertions in the late term group, respectively. The frequency of catheter-related bloodstream infection (CRBSI) was 1.98/1000 catheter days and 2.17/1000 catheter days in the early- and late term groups, respectively. In the subgroup analysis, the detected causative pathogens of CRBSI did not differ between the two term groups; gram-positive cocci, gram-positive bacilli, and gram-negative bacilli were the causative pathogens in 68.9, 11.5, and 14.8% of the cases in the early term group and in 68.2, 11.4, and 18.2% of the cases in the late term group, respectively. In the multivariate analysis to determine the risk of CRBSI, only age was detected as an independent contributing factor; the indwelling catheter duration was detected as a marginal factor. A significant reduction in mechanical complications was associated with the use of ultrasound guidance.

Conclusions

Ultrasound-guided CVC insertion did not decrease the incidence of CRBSI. The only identified risk factor for CRBSI was age in our cohort. However, we found that the introduction of ultrasound-guided insertion triggered an overall change in safety management with or without the physicians’ intent.

Recommendations on the Use of Ultrasound Guidance for Central and Peripheral Vascular Access in Adults: A Position Statement of the Society of Hospital Medicine

PREPROCEDURE

1)We recommend that providers should be familiar with the operation of their specific ultrasound machine prior to initiation of a vascular access procedure. 2)We recommend that providers should use a high-frequency linear transducer with a sterile sheath and sterile gel to perform vascular access procedures. 3)We recommend that providers should use two-dimensional ultrasound to evaluate for anatomical variations and absence of vascular thrombosis during preprocedural site selection. 4)We recommend that providers should evaluate the target blood vessel size and depth during preprocedural ultrasound evaluation.

TECHNIQUES

General Techniques 5) We recommend that providers should avoid using static ultrasound alone to mark the needle insertion site for vascular access procedures. 6)We recommend that providers should use real-time (dynamic), two-dimensional ultrasound guidance with a high-frequency linear transducer for central venous catheter (CVC) insertion, regardless of the provider's level of experience. 7)We suggest using either a transverse (short-axis) or longitudinal (long-axis) approach when performing real-time ultrasound-guided vascular access procedures. 8)We recommend that providers should visualize the needle tip and guidewire in the target vein prior to vessel dilatation. 9)To increase the success rate of ultrasound-guided vascular access procedures, we recommend that providers should utilize echogenic needles, plastic needle guides, and/or ultrasound beam steering when available. Central Venous Access Techniques 10) We recommend that providers should use a standardized procedure checklist that includes the use of real-time ultrasound guidance to reduce the risk of central line-associated bloodstream infection (CLABSI) from CVC insertion. 11)We recommend that providers should use real-time ultrasound guidance, combined with aseptic technique and maximal sterile barrier precautions, to reduce the incidence of infectious complications from CVC insertion. 12)We recommend that providers should use real-time ultrasound guidance for internal jugular vein catheterization, which reduces the risk of mechanical and infectious complications, the number of needle passes, and time to cannulation and increases overall procedure success rates. 13)We recommend that providers who routinely insert subclavian vein CVCs should use real-time ultrasound guidance, which has been shown to reduce the risk of mechanical complications and number of needle passes and increase overall procedure success rates compared with landmark-based techniques. 14)We recommend that providers should use real-time ultrasound guidance for femoral venous access, which has been shown to reduce the risk of arterial punctures and total procedure time and increase overall procedure success rates. Peripheral Venous Access Techniques 15) We recommend that providers should use real-time ultrasound guidance for the insertion of peripherally inserted central catheters (PICCs), which is associated with higher procedure success rates and may be more cost effective compared with landmark-based techniques. 16)We recommend that providers should use real-time ultrasound guidance for the placement of peripheral intravenous lines (PIV) in patients with difficult peripheral venous access to reduce the total procedure time, needle insertion attempts, and needle redirections. Ultrasound-guided PIV insertion is also an effective alternative to CVC insertion in patients with difficult venous access. 17)We suggest using real-time ultrasound guidance to reduce the risk of vascular, infectious, and neurological complications during PIV insertion, particularly in patients with difficult venous access. Arterial Access Techniques 18)We recommend that providers should use real-time ultrasound guidance for arterial access, which has been shown to increase first-pass success rates, reduce the time to cannulation, and reduce the risk of hematoma development compared with landmark-based techniques. 19)We recommend that providers should use real-time ultrasound guidance for femoral arterial access, which has been shown to increase first-pass success rates and reduce the risk of vascular complications. 20)We recommend that providers should use real-time ultrasound guidance for radial arterial access, which has been shown to increase first-pass success rates, reduce the time to successful cannulation, and reduce the risk of complications compared with landmark-based techniques.

POSTPROCEDURE

21) We recommend that post-procedure pneumothorax should be ruled out by the detection of bilateral lung sliding using a high-frequency linear transducer before and after insertion of internal jugular and subclavian vein CVCs. 22)We recommend that providers should use ultrasound with rapid infusion of agitated saline to visualize a right atrial swirl sign (RASS) for detecting catheter tip misplacement during CVC insertion. The use of RASS to detect the catheter tip may be considered an advanced skill that requires specific training and expertise.

TRAINING

23) To reduce the risk of mechanical and infectious complications, we recommend that novice providers should complete a systematic training program that includes a combination of simulation-based practice, supervised insertion on patients, and evaluation by an expert operator before attempting ultrasound-guided CVC insertion independently on patients. 24)We recommend that cognitive training in ultrasound-guided CVC insertion should include basic anatomy, ultrasound physics, ultrasound machine knobology, fundamentals of image acquisition and interpretation, detection and management of procedural complications, infection prevention strategies, and pathways to attain competency. 25)We recommend that trainees should demonstrate minimal competence before placing ultrasound-guided CVCs independently. A minimum number of CVC insertions may inform this determination, but a proctored assessment of competence is most important. 26)We recommend that didactic and hands-on training for trainees should coincide with anticipated times of increased performance of vascular access procedures. Refresher training sessions should be offered periodically. 27)We recommend that competency assessments should include formal evaluation of knowledge and technical skills using standardized assessment tools. 28)We recommend that competency assessments should evaluate for proficiency in the following knowledge and skills of CVC insertion: (a) Knowledge of the target vein anatomy, proper vessel identification, and recognition of anatomical variants; (b) Demonstration of CVC insertion with no technical errors based on a procedural checklist; (c) Recognition and management of acute complications, including emergency management of life-threatening complications; (d) Real-time needle tip tracking with ultrasound and cannulation on the first attempt in at least five consecutive simulation. 29)We recommend a periodic proficiency assessment of all operators should be conducted to ensure maintenance of competency.

Risk factors for a difficult intravenous access: A multicentre study comparing nurses' beliefs to evidence

AIMS AND OBJECTIVES

To summarise the evidence about patient-related risk factors for difficult intravenous access in adults, and at identifying nurses' beliefs and their consistency with evidence.

BACKGROUND

Peripheral intravenous cannulation is a common procedure for nurses, but rates of failure at first attempt of peripheral intravenous cannulation range 10%-40%. Nurses' beliefs about difficult intravenous access factors might influence their clinical practice more than current evidence.

DESIGN

The study included a literature review of the evidence on patient-related risk factors for difficult intravenous access, the development of an instrument to investigate nurses' beliefs about this topic and a cross-sectional multicentre survey on clinical nurses.

METHODS

The quality of the studies included was evaluated through the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. A synthesis of evidence for each risk factor was produced. A survey instrument was developed including 26 risk factors, which were then rated by nurses as perceived predictors of difficult intravenous access. The STROBE guidelines for study reporting were followed.

RESULTS

Four hundred and fifty clinical nurses working in four hospitals in Italy were surveyed. Nurses' beliefs were in line with evidence in considering body mass index, drug abuse, lymphadenectomy and chemotherapy as difficult intravenous access factors. Beliefs about difficult intravenous access factors were influenced by nurses' work experience and frequency of peripheral intravenous cannulation. Nurses also identified as risk factors for difficult intravenous access oedema, thrombophlebitis, hypovolaemia, skin lesions and irritant therapies, which have been minimally investigated by research.

CONCLUSIONS

An overall congruence between nurses' beliefs and evidence about risk factors for difficult intravenous access was found. With their expertise, nurses may fill the knowledge gap of clinical evidence and open new paths for clinically meaningful research.

RELEVANCE TO CLINICAL PRACTICE

Nurses' beliefs about difficult intravenous access factors can be influenced by their work experience and clinical setting. Integrating nurses' beliefs with scientific evidence can increase the quality of care.

Where is the Guidewire? Confirmation of Central Catheter Placement in the Brachiocephalic Vein Using Y-shape Visualization by Ultrasound

Central venous catheter placement with ultrasound guidance improves the success rate and reduces the number of puncture attempts and complications. Y-shape visualization of central veins using an endocavity micro-convex ultrasound probe is a new technique, which has been used for brachiocephalic vein cannulation. Since the jugular, subclavian, and brachiocephalic veins can be visualized in a single view using the Y-shape technique, it can also be used to confirm the correct placement of the catheter or guidewire. We aimed to present a case in which the location of the guidewire was verified by Y-shape visualization with an endocavity micro-convex probe after a cannulation attempt. Successful internal jugular vein catheterization was achieved with the assistance of the Y-shape imaging technique and the patient was avoided from multiple cannulation attempts.

Peripherally inserted central catheters in critically ill patients - complications and its prevention: A review

Peripherally inserted central catheter (PICC) is extensively used in critical care settings, because it plays a vital role in providing safe central venous entry. However, PICC is associated with several complications, which should be detected to shorten the duration of patients' improvement, reduce health care cost, and lessen the incidence of various PICC-related complications. Therefore, this study aimed to outline current literature on PICC procedures, potential complications, and measures for prevention. Understanding evidence-based guidelines regarding insertion technique, early detection of complications, and care bundle of PICC is significant in complication prevention. Implementation of education, training, and appropriate multidisciplinary approaches on PICC care among nurses and caregivers is the key to preventing complications. Thus, the strict care of indwelling PICC lines, the targeted and reasonable PICC-associated complication prevention, and nursing care have a major clinical significance in reducing the occurrence of potential PICC complications.

Traditional and ultrasound physical examinations: a hybrid approach to improve clinical care

Point-of-care ultrasonography, which is performed at the bedside by physicians who are not specialists in imaging, has become possible thanks to recent technological advances that have allowed for a device with greater portability while maintaining image quality. The increasing use of point-of-care ultrasonography in different specialties has made it possible to expand physical examinations, make timely decisions about the patients and allows the performance of safer medical procedures. In this review, three cases from our experience are presented that highlight the use of point-of-care ultrasonography by clinicians. Bedside ultrasonography is a convenient modality used in a clinical setting to aid in early diagnosis of several common conditions. It is suggested that a hybrid approach of physical examination and point-of-care ultrasonography in the everyday clinical practice is an inevitable change of paradigm that is improving quality of care in a variety of clinical settings.

Impact of point-of-care ultrasound on clinical decision-making at an urban emergency department in Tanzania

BACKGROUND

Point of care ultrasound (PoCUS) is an efficient, inexpensive, safe, and portable imaging modality that can be particularly useful in resource-limited settings. However, its impact on clinical decision making in such settings has not been well studied. The objective of this study is to describe the utilization and impact of PoCUS on clinical decision making at an urban emergency department in Dar es Salaam, Tanzania.

METHODS

This was a prospective descriptive cross-sectional study of patients receiving PoCUS at Muhimbili National Hospital's Emergency Medical Department (MNH EMD). Data on PoCUS studies during a period of 10 months at MNH EMD was collected on consecutive patients during periods when research assistants were available. Data collected included patient age and sex, indications for ultrasound, findings, interpretations, and provider-reported diagnostic impression and disposition plan before and after PoCUS. Descriptive statistics, including medians and interquartile ranges, and counts and percentages, are reported. Pearson chi squared tests and p-values were used to evaluate categorical data for significant differences.

RESULTS

PoCUS data was collected for 986 studies performed on 784 patients. Median patient age was 32 years; 56% of patients were male. Top indications for PoCUS included trauma, respiratory presentations, and abdomino-pelvic pain. The most frequent study types performed were eFAST, cardiac, and obstetric or gynaecologic studies. Overall, clinicians reported that the use of PoCUS changed either diagnostic impression or disposition plan in 29% of all cases. Rates of change in diagnostic impression or disposition plan increased to 45% in patients for whom more than one PoCUS study type was performed.

CONCLUSIONS

In resource-limited emergency care settings, PoCUS can be utilized for a wide range of indications and has substantial impact on clinical decision making, especially when more than one study type is performed.

Arterial Compression of Left Iliac Veins: Five-Year Patency Rates of Endovascular Treatment

Endovascular angioplasty and stenting have become a treatment of choice for severely symptomatic left iliac veins under external, arterial compression. Patency rates of stented iliac veins based on ultrasonographic (US) findings were estimated. Retrospective analyses of gender, age, deep venous thrombosis (DVT) prior to stenting, stent location at common and/or external iliac veins, and patency rates from 1 month to 5 years were performed. Patients treated were mostly women (72 of 79, 91%), aged 51 ± 16 (25-89) years. Patency rates were 96% at 1 month, 89% at 1 year, and 85% at 3 to 5 years, best for common iliac, 95%, than for external iliac vein stents, subgroup with prior DVT, with secondary patency rates of 75%. US demonstrated acceptable patency rates for iliac vein stenting showing good performance for common iliac vein stents but a decreased performance with stent extending to the external iliac vein or stents placed in patients with prior iliac DVT.

How useful is ultrasound guidance for internal jugular venous access in children?

PURPOSE

The aim of this study was to determine whether US reduces number of puncture attempts, procedure time, and complication rate during IJV access in children.

METHODS

A prospective study was performed in children (age ≤18years) admitted to our institution, from September 2013 to July 2014, with indications for central venous access. Patients meeting the inclusion criteria were randomized to the US-guided or control groups. The same physician performed all IJV cannulations in both groups. The end-points for comparison were: length of time to venous access, number of attempts, and rate of complications.

RESULTS

Fifty-one patients were included: 23 in the US-guided group and 28 in the control group. There were no between-group differences in weight, age, or sex. In the US-guided group, the number of punctures needed to achieve IJV access (median [interquartile range], 3 [2-5] vs. 1 [1, 2]; P<0.001), time to achievement of venous access, and complication rate (39% vs. 4.3%, P<0.009) were significantly lower.

CONCLUSION

US guidance is a useful adjunct to central venous access in children, facilitating the procedure, decreasing time to cannulation, and increasing safety.

TYPE OF STUDY

Prospective randomized study.

LEVEL OF EVIDENCE

1.

Bedside ultrasound to detect central venous catheter misplacement and associated iatrogenic complications: a systematic review and meta-analysis

Background

Insertion of a central venous catheter (CVC) is common practice in critical care medicine. Complications arising from CVC placement are mostly due to a pneumothorax or malposition. Correct position is currently confirmed by chest x-ray, while ultrasonography might be a more suitable option. We performed a meta-analysis of the available studies with the primary aim of synthesizing information regarding detection of CVC-related complications and misplacement using ultrasound (US).

Methods

This is a systematic review and meta-analysis registered at PROSPERO (CRD42016050698). PubMed, EMBASE, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials were searched. Articles which reported the diagnostic accuracy of US in detecting the position of CVCs and the mechanical complications associated with insertion were included. Primary outcomes were specificity and sensitivity of US. Secondary outcomes included prevalence of malposition and pneumothorax, feasibility of US examination, and time to perform and interpret both US and chest x-ray. A qualitative assessment was performed using the QUADAS-2 tool.

Results

We included 25 studies with a total of 2548 patients and 2602 CVC placements. Analysis yielded a pooled specificity of 98.9 (95% confidence interval (CI): 97.8–99.5) and sensitivity of 68.2 (95% CI: 54.4–79.4). US examination was feasible in 96.8% of the cases. The prevalence of CVC malposition and pneumothorax was 6.8% and 1.1%, respectively. The mean time for US performance was 2.83 min (95% CI: 2.77–2.89 min) min, while chest x-ray performance took 34.7 min (95% CI: 32.6–36.7 min). US was feasible in 97%. Further analyses were performed by defining subgroups based on the different utilized US protocols and on intra-atrial and extra-atrial misplacement. Vascular US combined with transthoracic echocardiography was most accurate.

Conclusions

US is an accurate and feasible diagnostic modality to detect CVC malposition and iatrogenic pneumothorax. Advantages of US over chest x-ray are that it can be performed faster and does not subject patients to radiation. Vascular US combined with transthoracic echocardiography is advised. However, the results need to be interpreted with caution since included studies were often underpowered and had methodological limitations. A large multicenter study investigating optimal US protocol, among other things, is needed.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-1989-x) contains supplementary material, which is available to authorized users.

A Rare Vascular Anomaly during Central Venous Catheterization: A Persistent Left-Sided Superior Vena Cava

A persistent left-sided superior vena cava (PLSVC) is the most frequent abnormality of the venous system; however, it is not a very well-known variation among physicians. Herein we report the case of a patient with a PLSVC who was diagnosed after central venous catheterization (CVC). An 80-year-old man was admitted to the emergency room with cardiopulmonary arrest. After the return of spontaneous circulation, CVC was blindly performed from the left jugular vein without any complications. However, routine chest X-ray after catheterization revealed that the catheter was moving down directly to the left heart. Thoracic computed tomography showed the right brachiocephalic vein draining into the left brachiocephalic vein and forming the left superior vena cava in front of the aortic arch. The left superior vena cava merged into the right atrium after crossing the left pulmonary artery. CVC is widely used in clinical practice, and therefore clinicians should be aware of possible variations in central veins, particularly during blind catheterization.

Usefulness of Doppler waveform analysis before performing a complex procedure using femoral venous access

Ultrasonography is a well-defined and widely accepted technique in the settings of interventional procedures requiring peripheral venous access, either for the confirmation of the vein patency (with the compression test) or for guiding needle insertion. This report describes a case of unsuccessful guidewire passage through the right iliac vein in spite of successful ultrasonography-guided puncture of the femoral vein. On repeat duplex ultrasonography, the Doppler waveform showed a continuous pattern without respiratory phasicity, which was consistent with proximal venous occlusion. Venous Doppler signal waveform analysis can be helpful for ensuring downstream patency when planning long-distance catheterization via femoral venous access.

Supraclavicular Approach to Ultrasound-Guided Brachiocephalic Vein Cannulation in Children and Neonates

The correct choice of intra vascular access in critically ill neonates should be individualized depending on the type and duration of therapy, gestational and chronological age, weight and/or size, diagnosis, clinical status, and venous system patency. Accordingly, there is an ongoing demand for optimization of catheterization. Recently, the use of ultrasound (US)-guided cannulation of the subclavian vein (SCV) has been described in children and neonates. This article gives an overview of the current use of US for achieving central venous catheter placement in the SCV or the brachiocephalic vein (BCV) in neonates. More than 1,250 catheters have been reported inserted in children and neonates for a cumulated success rate of 98.4% and the complication rate is reported to be low. The technical aspects of various approaches are discussed, and we offer our recommendation of an US-guided technique for SCV and BCV cannulation based on our experience in a large NICU setting. Although the cannulation the SCV or BCV does not substitute the use of peripherally inserted central catheters or umbilical venous central catheters in neonates, it is a feasible route in very small children who are in need of a large caliber central venous access.

Bedside ultrasound training at Muhimbili National Hospital in Dar es Salaam, Tanzania and Hospital San Carlos in Chiapas, Mexico

INTRODUCTION

In resource-rich settings, bedside ultrasound has rapidly evolved to be a crucial part of emergency centre practice and a growing part of critical care practice. This portable and affordable technology may be even more valuable in resource-limited environments where other imaging modalities are inaccessible, but the optimal amount of training required to achieve competency in bedside ultrasound is largely unknown. We sought to evaluate the feasibility of implementation of a mixed-modality bedside ultrasound training course for emergency and generalist acute care physicians in limited resource settings, and to provide a description of our core course components, including specific performance goals, to facilitate implementation of similar initiatives.

METHODS

We conducted a standardised training course at two distinct sites-one large, urban tertiary hospital in Tanzania with a dedicated Emergency Centre, and one small, rural, hospital in southern Mexico with a general, acute intake area. We report on pre-training ultrasound use at both sites, as well as pre- and post-training views on most useful indications.

RESULTS

Overall, participants were very satisfied with the course, although approximately one-third of the providers at both sites would have preferred more hands-on training. All participants passed a standardised exam requiring image acquisition and interpretation.

DISCUSSION

Introducing bedside ultrasound training in two distinct resource-limited settings was feasible and well-received. After a brief intensive period of training, participants successfully passed a comprehensive examination, including demonstration of standardised image acquisition and accurate interpretation of normal and abnormal studies.

Ultrasound-guided central vascular interventions, comments on the European Federation of Societies for Ultrasound in Medicine and Biology guidelines on interventional ultrasound

Central venous access has traditionally been performed on the basis of designated anatomical landmarks. However, due to patients' individual anatomy and vessel pathology and depending on individual operators' skill, this landmark approach is associated with a significant failure rate and complication risk. There is substantial evidence demonstrating significant improvement in effectiveness and safety of vascular access by realtime ultrasound (US)-guidance, as compared to the anatomical landmark-guided approach. This review comments on the evidence-based recommendations on US-guided vascular access which have been published recently within the framework of Guidelines on Interventional Ultrasound (InVUS) of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) from a clinical practice point of view.

The role of ultrasound guidance for vascular access

PURPOSE OF REVIEW

Ultrasound-guided cannulation of the internal jugular vein has become a standard practice over recent years. Despite known benefits, ultrasound is less frequently used for other vascular applications probably because these are technically demanding and require more experience. The authors of this review focus on pitfalls of ultrasound guidance: most important practical aspects as well as nonroutine vascular applications are discussed.

RECENT FINDINGS

Ultrasound guidance increases the first-pass and overall success rates and reduces the risk of complications of central venous catheterization through the subclavian and femoral routes, as well as arterial and difficult peripheral venous access. Ultrasound is also useful to detect catheter malposition and complications. Technical improvements and new modifications of old ultrasound-guided techniques may result in better outcomes.

SUMMARY

Growing evidence suggests that routine utilization of ultrasound guidance is beneficial for all types of vascular access. The presence of a skilled operator and proper technique are, however, required to achieve success and avoid complications.

[Application of ultrasonography in central venous catheterization; access sites and procedure techniques]

Central venous catheterization is commonly performed in clinical practice. Traditional procedural technique is based on anatomical landmarks, but is associated with a high risk of failure and complications. To decrease their incidence European and American societies recommend application of ultrasonography. Preliminary ultrasonographic examination allows for assessment of local anatomical relations as well as vessel morphology (diameter, patency), while real-time ultrasonography increases chances of successful needle insertion. This paper presents the most common venous access sites and procedure techniques.

Comparison of two ultrasound guided approaches for axillary vein catheterization: a randomized controlled non-inferiority trial

BACKGROUND

Axillary vein catheterization via a distal approach is an alternative to the proximal approach to axillary/subclavian vein catheterization under ultrasound (US) guidance. The aim of this trial was to compare the two approaches.

METHODS

In a randomized single-centre study, all patients requiring central vein catheterization in intensive care or the operating room were randomly assigned to proximal or distal approach groups. If catheterization failed after two attempts using the approach allocated, the non-allocated approach was used. The primary endpoint was the initial success rate of distal to compared with the proximal approach, using a non-inferiority analysis (lower limit 90% CI greater than -8% non-inferiority margin for group difference). The secondary endpoints were: overall success rates, catheter position and complications.

RESULTS

119/122 included patients were analysed (57 and 62 in the proximal and distal axillary approach groups, respectively). Primary success rates for proximal and distal sites were 87.7 and 85.5%, respectively (difference -2.2%, 90% CI [-12.5-8.1%], non-inferiority P=0.18). The proximal and distal overall success rates were 96.5 and 98.4%, respectively (difference -1.9%, 90% CI [-4.9-8.7%], non-inferiority P<0.01). Thrombogenic catheter positions were 7 (12.3%) in proximal approach group vs 19 (31.7%) in the distal approach group (P=0.01). Complications were comparable in the two groups (2 (3.3%) vs 4 (6.5%), P=0.68).

CONCLUSION

In terms of absolute and overall success rates, a distal approach is not non-inferior to a proximal approach. Although associated with a more thrombogenic catheter extremity position, the distal approach can be considered as a rescue alternative after failure of a proximal approach.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01543360.

Standard Procedures of Endovascular Treatment for Vascular Access Stenosis in our Facility – Clinical Usefulness of Ultrasonography

In Japan, the number of patients receiving dialysis is 314,180 at the end of 2013 and 97% are treated with hemodialysis. And the mean age of patients and the percentage of diabetes have been increasing. For this reason, preparations of a new vascular access (VA) and its long-term maintenance have become difficult. In the guidelines by the Japanese Society for Dialysis Therapy (JSDT), endovascular treatment (ET) is positioned as the first line for VA stenosis. The procedure of ET itself is very simple. The revision of Japanese health insurance set an expensive technical fee for ET in 2012. It also added a restriction by which the claims for both technical and material fees would be denied, if the treatment was performed within 3 months after a previous treatment. This makes determination of best treatment timing more important. The functional evaluation using ultrasonography (US) is a useful monitoring index for determination of the ET timing for patients with stenosis. We investigated the cumulative relative frequency of flow volume (FV) and resistant index (RI) of brachial artery in arteriovenous graft (AVG) and arteriovenous fistula (AVF) cases with access failures. As a result, the cut-off values of FV and RI in AVG were 480 mL/min and 0.57, and in AVF were 354 mL/min and 0.61, respectively. Therefore we determine the treatment timing based on these results. Since 2012, active monitoring using US could have decreased the number of treatment patients by 100 per year. This meant that objective evaluation by US enabled treatments at a more suitable time to promote the proper use of medical expenses for EV treatment.

Ultrasonographic comparison of two landmarks for the internal jugular vein: high versus conventional approach

OBJECTIVE

We assessed and compared two landmarks (conventional vs. high approach) used in internal jugular vein (IJV) cannulation with respect to the degree of overlap with the carotid artery (CA) and the cross-sectional area (CSA) of the IJV using ultrasonography.

PATIENTS AND METHODS

Forty-eight adult patients were included. Using ultrasonography, the percentage overlaps with the CA and the CSA of both IJVs were measured in the supine and Trendelenburg positions using conventional and high approaches. With the conventional approach, the IJV is penetrated at the apex of Sedillot's triangle, formed by the clavicle and the sternal and clavicular heads of the sternocleidomastoid muscle. The high approach involves the midpoint between the sternal notch and the mastoid process.

RESULTS

The degree of overlap with the CA was 30.5 (7.5-69.4)% [median (interquartile range)] and 0.0 (0.0-25.4)% with the conventional and high approaches, respectively, for the right IJV (P<0.001) in the Trendelenburg position with 30° head rotation. The CSA of the right IJV was 1.22 (0.92-2.01) and 0.98 (0.79-1.72) cm with the conventional and high approaches, respectively (P<0.001), in the Trendelenburg position with 30° head rotation. IJV was more deeply positioned using the high approach than the conventional approach (P<0.001).

CONCLUSION

The high approach for IJV cannulation decreased both the degree of overlap with the CA and CSA of the IJV and increased the depth of the IJV from the skin compared with the conventional approach.